Acryloyloxy-terminated polydimethylsiloxane (AC-PDMS)-based thin-film composite (TFC) membrane, and preparation method and use thereof

A preparation method of an acryloyloxy-terminated polydimethylsiloxane (PDMS)-based thin-film composite membrane, wherein the acryloyloxy-terminated PDMS-based thin-film composite membrane comprises a support layer, and a selective separation layer on a surface of the support layer, and the selective separation layer has a structure shown as follows:

• wherein R is linear or branched alkyl with 1 to 16 carbon atoms;
• the acryloyloxy-terminated PDMS-based thin-film composite membrane is used in gas separation;
• and
• the preparation method comprises following steps:
• step 1:
• dissolving acryloyloxy-terminated PDMS and a photoinitiator in a solvent to obtain a casting solution;
• and
• step 2:
• coating the casting solution on the surface of the support layer, conducting ultraviolet irradiation to cure the acryloyloxy-terminated PDMS to obtain a resulting product, and subjecting the resulting product to a heat treatment at 60° C. to 90° C. for 5 min to 30 min to evaporate away excess solvent to obtain the PDMS-based thin-film composite membrane,
• wherein in the step 1, a concentration of the acryloyloxy-terminated PDMS in the casting solution is 1 wt % to 25 wt %, a weight ratio of the acryloyloxy-terminated PDMS to the photoinitiator is (5-15):1, the solvent is a non-polar solvent, and the non-polar solvent is a hydrocarbon solvent or an ester solvent;
• the step 1 further comprises adjustment of a viscosity of the casting solution by subjecting the casting solution to intermittent ultraviolet irradiation and stirring to control the viscosity of the casting solution at 35 cP to 55 cP;
• and
• the acryloyloxy-terminated PDMS has a structure shown as follows:
• wherein R is linear or branched alkyl with 1 to 16 carbon atoms;
• and
• in the step 2, the support layer is subjected to a water-filling treatment in advance, the ultraviolet irradiation is conducted for 1 s to 30 s, and ultraviolet light for the ultraviolet irradiation is one selected from a group consisting of ultraviolet A (UVA), ultraviolet B (UVB), and ultraviolet C (UVC), or mixed light of two or more thereof.